Lake turnover in temperate locations results in: Group of answer choices A. freezing of water from the bottom of the lake up to the top. B. loss of organisms living in a lake. C. stagnation of water and diversity of anaerobic organisms in the lake. D. decrease of oxygen and nutrients throughout the lake. E. mixing of oxygen and nutrients throughout the lake.

Students from Westbury High School participated in a study of the Willow Waterhole Pond. After safely taking samples of some small fish, a fish-eating hawk, some pond water, some zooplankton, and a fish that preys on the small fish, they determined the average concentration of compound "Z" in each sample. The table below summarizes their data.   Build a food chain that illustrates the correct trophic order in the pond. Include the concentrations of compound "Z" for each part of the chain. Describe one natural process that would cause compound "Z" to contaminate the pond's water. (Please write in complete sentences.)

Flux of anthropogenic Phosphorous from terrestrial to aquatic ecosystems can have negative effects, such as A. Eutrophication B. Ocean acidification C. Acid rain D. Both A and C E. A, B and C

Water is less dense as a solid than as a liquid. How does this property typically affect a lake ecosystem in freezing temperatures? O When the lake is frozen, fish still have access to liquid water for oxygen and swimming as well as access to food on the bottom of the lake O When the lake is frozen, fish still have access to liquid water for oxygen and swimming but no longer have access to food on the bottom of the lake. O When the lake is frozen, fish no longer have access to liquid water for oxygen and swimmng but do have access to food on the bottom of the lake. O When the lake is frozen, fish no longer have access to liquid water for oxygen and swimming and no longer have access to food on the bottom of the lake